The present invention generally relates to the field of portable insulated containers and particularly for a structural support for such device having active or passive heat transfer systems.
There are many different types of portable insulated containers on the market today. One common type of portable insulated containers is made of rigid materials. These insulated containers are sturdy, durable, and good insulators. Another common type of portable insulated containers is made of soft and flexible materials. The prior art U.S. Pat. No. 6,332,712 B1 describes a sealed bag made of flexible plastic, unlike a rigid container, the flexible bag described can fold onto itself. This second type of portable insulated container is lightweight and easy to carry. Another prior art as described in U.S. Pat. No. 4,537,313 provides a soft foldable container with improved insulation. This later type is lightweight, easy to carry, and good insulators.
These prior arts utilize passive heat transfer as the insulting means; others rely on active and passive heat transfer as the insulating mean. Prior art U.S. Pat. No. 6,206,646 presents another insulated container made of flexible insulating materials and a thermoelectric element as the active cooling mean.
A major disadvantage of rigid type containers is that they can be quite cumbersome and do not allow adaptability to the wide range of content users might want to place in such device. On the other hand, flexible containers are much less invasive, and adapt to a wider range of use and locations. Unfortunately, because of the flexible property of such containers, they easily deform drastically limiting the carrying capacity and have a limited lifetime. Another disadvantage is the poor insulating performance of flexible containers. The construction of portable active cooling containers does not allow passive cooling as the alternate cooling mean; even less so simultaneously as the use of ice as the cooling mean would damage the conventional active cooling system of such portable containers.